Elliott Sober’s new book, Evidence and Evolution: The Logic Behind the Science, now available

cbearden: "Regarding the evidence for common descent from e.g. sequence data: surely such evidence is logically compatible with descent from a common ancestor by purely naturalistic processes, but unless it is also logically inconsistent with a designer having guided or caused the emergence and development of life forms, it can’t be taken as deductive evidence against ID." I'm not offering it as such. "Since there seems to be no reason to think the evidence logically inconsistent with a designer,..." Why would you make such a claim without examining the evidence for yourself? "... then this evidence must be taken by the Darwinist as providing inductive evidence against ID instead:..." You're employing a false dichotomy. The evidence is there, and the IDist must explain it. "... that is, the evidence must be taken as being substantially more probable with respect to NDE than with respect to ID. How does the Darwinist thinker go about making a rigorous inductive case against ID based on the sequence evidence?" Why are you so eager to feign familiarity with this evidence? How does the ID thinker go about dealing with this evidence? Shouldn't it give us some idea as to when design events occurred? "What is it about this evidence that makes NDE sufficiently more probable with respect to NDE than ID, such that one is warranted in regarding it as evidence against ID? That’s a sincere question–I don’t presume to know the answer." You've already presumed too much. For example, how does your particular design hypothesis explain the accumulation of nonfunctional differences (not nonfunctional sequences, but differences) over time? Russell

Leo: "Russell: the sequence evidence may give evidence for the thesis that species have developed by way of descent from a common ancestor." May? No, it does, but you're still misrepresenting the precision it provides. Again, many in the ID movement, including Mike Behe and DaveScot, do not dispute common descent. "But how does it give evidence that the process of common descent was caused by natural selection acting on chance variation (rather than, say, by a designer)?" Because no set of designed objects fits ONLY ONE nested hierarchy, and even more importantly, the components fit the same hierarchy as the organisms. You're also missing another point: much of the sequence variation is caused by non-Darwinian mechanisms, so there is another important reason to examine this evidence (and not merely what anyone else says about it) carefully. Russell

Commenting on Ekstasis's contention that "anything we believe should be based on evidence that can be tested": I take it you mean that any scientific beliefs should be based on evidence that can be tested. This assertion cannot be true of all rational beliefs unless you think that relationships of evidential support among beliefs can ultimately be circular, or unless you think that humans can entertain an infinite number of beliefs. Regarding the evidence for common descent from e.g. sequence data: surely such evidence is logically compatible with descent from a common ancestor by purely naturalistic processes, but unless it is also logically inconsistent with a designer having guided or caused the emergence and development of life forms, it can't be taken as deductive evidence against ID. Since there seems to be no reason to think the evidence logically inconsistent with a designer, then this evidence must be taken by the Darwinist as providing inductive evidence against ID instead: that is, the evidence must be taken as being substantially more probable with respect to NDE than with respect to ID. How does the Darwinist thinker go about making a rigorous inductive case against ID based on the sequence evidence? What is it about this evidence that makes NDE sufficiently more probable with respect to NDE than ID, such that one is warranted in regarding it as evidence against ID? That's a sincere question--I don't presume to know the answer. cbearden

Re: post #3 Also, how was the DNA sequence, say, of hydrophillic molecules, built up through a gradually slow mutation and selection process without causing a disruption in the code of the other disassociated molecules? Similar blueprints can also point to common design. Why should a disign principle that is working perfectly well be changed to that of another that may be less optimal? Sequence similarity doesn't prove DE as much as it doesn't disprove IDT. JPCollado

Russell: the sequence evidence may give evidence for the thesis that species have developed by way of descent from a common ancestor. But how does it give evidence that the process of common descent was caused by natural selection acting on chance variation (rather than, say, by a designer)? Leo Hales

"Golly gee, how should we score such evidence as varying beak lengths in order to explain the emergence of phyla, species, new organs, and the human brain?" I don't think anyone claims to be relying on beak lengths. It seems that scientists actually rely on the sequence evidence. Russell

I have not read the book, but it seems to focus heavily on the nature of evidence for Darwinian evolution, and the testability of ID. This is key, since anything we believe should be based on evidence that can be tested. Which brings up a thought provoking parallel. In the intelligence community one does not simply gather evidence, present it, and draw broad conclusions. Why? Because national security and lives are at stake. No indeed, evidence is evaluated and graded according to a perceived level of reliability. Factors such as the source of the information, colloborating evidence, consistency with other information, etc is considered. Significant evidence is then awarded a confidence score. Now, imagine if we applied the same due diligence to NDE. Golly gee, how should we score such evidence as varying beak lengths in order to explain the emergence of phyla, species, new organs, and the human brain? Or the idea that one biological constuct is co-opted for other purposes? Incredible, is it not? I am just thankful to the designer, or the directionless cosmos if you prefer, that this crowd is not in charge of national security. We would be in a heap of trouble. Ekstasis